(2x-3)(2x+3)-1=5x+(x-2)²

Question

(2x-3)(2x+3)-1=5x+(x-2)²

Answer 1

(2х-3)(2х+3)-1=5х+(х-2)²
(2х)²-3²-1=5х+(х²-4х+4)
4х²-9-1=5х+х²-4х+4
4х²-х²-5х+4х-9-1-4=0
3х²-х-14=0
D=(-x)²-4*3*(-14)=1+168=169
x₁=(1+13)\2=14\2=7
x₂=(1-13)\2=-12\2=-6
Ответ:-6